Can I use a ski travel backpack as my only ski bag for a flight?

It depends on the airline and the pack size. Most ski travel backpacks (40–55L) exceed standard carry-on size limits, so you'll likely need to check the bag. Some airlines have specific sports equipment policies that allow ski bags as checked items for a fee. If you want to avoid checked bag fees, look for packs under 40L that compress to airline carry-on dimensions, though you may need to strap skis to the outside. Always check your specific airline's baggage policy before flying.